Apparatus for treating tobacco and the like



sept. s, 196s H. KOCH ETAI- APPARATUS FOR TREATING TOBACCO AND THE LIKEFiled July 29, 1966 Inventors United States Patent O 3,399,462 APPARATUSFOR TREATING TOBACC AND THE LIKE Hans Koch, Hamburg-Rahlstedt, WaldemarWochnowski, Hamburg, Willi Thiele, Geesthacht-Tesperhude, and GustavHaneke, Hamburg, Germany, assignors to Hanni-Werke Koerber & Co., KG.,Hamburg-Bergedorf, Germany Filed July 29, 1966, Ser. No. 568,782 Claimspriority, application Germany, Aug. 4, i965,

1o claims. (in. 31a-57) ABSTRACT F THE DISCLOSURE Apparatus for feedingtobacco to a drier comprises a first conveyor which converts acontinuous tobacco stream into a series of batches and dumps suchbatches into a vibrating trough wherein the batches are converted intoan equalized mat. The leading end of the mat is fed into the drier.

The present invention relates to apparatus for treating tobacco leafstock or other types of owable solid materials. More particularly, theinvention relates to improvements in apparatus which may be utilized forexpelling surplus moisture from destalked or from destalked and shreddedtobacco leaf laminae. Still more particularly, the invention relates toimprovements in such parts or units of a tobacco drying or roastingapparatus which are utilized to feed tobacco into a drier wherein thetobacco particles are treated by contact with hot air or anothersuitable gaseous medium.

An apparatus which is utilized for drying or roasting of tobacco mustmeet two important requirements one of which includes proper temperaturecontrol of the heating medium and the other of which includes properfeed of tobacco into the drying or conditioning chamber. Our presentinvention is particularly concerned with improvements in such parts orunits of a tobacco drying or roasting apparatus which are utilized toinsure satisfactory admission of tobacco particles into a current of hotair or another gas. The importance of proper feed of tobacco into thedrying or conditioning chamber of a drier will be readily understood byconsidering that even small variations in the rat-e of admission willresult in excessive or insuicient expulsion of moisture so that theparticles issuing from the conditioning chamber are too dry or containexcessive amounts of moisture. Even if the temperature D of the hot gasis regulated in accordance with measurements which are carried out todetermine the moisture content of successive increments of the tobaccostream prior and/0r subsequent to drying, the inertia of various signalgenerating, transmitting and adjusting instrumentalities prevents timelyadjustments in the temperature of hot gas. On the other hand, tobaccoleaf stock which is stored for curing in the form of bales or inreceptacles must have a moisture content which is within a very narrowrange because, otherwise, the laminae will disintegrate if the moisturecontent is too low or will spoil in storage if the moisture content istoo high. The manufacturers of cigarettes, cigars and similartobacco-containing articles also insist that the moisture content ofshredded tobacco should be within a narrow range such as is desirable toprevent excessive breakage of dry shreds or excessive adherence of moistshreds to each other.

Accordingly, it is an important object of the present invention toprovide a tobacco drying or conditioning apparatus with novel andimproved conveyor means which are constructed and arranged in such laway that they can feed to the conditioning chamber of a drier asuccession Patented Sept. 3, 1968 ICC of increments each of whichcontains the same amount 0f tobacco.

Another object of the invention is to provide an apparatus for treatmentof owable material, particularly for drying of shredded or destalkedtobacco lea-f laminae, which can convert a continuous or discontinuoustobacco stream wherein successive increments might but need not `containthe same amounts of material into a different stream (which may resemblea carpet or mat) and which is fully equalized before the leading end ofsuch different stream reaches its destination, for example, the dryingor conditioning chamber of a drier.

A further object of the invention is to provide an apparatus of the justoutlined characteristics wherein the conversion of a stream of owablematerial into an equalized mat can be readily observed at 'all times andwherein eventual inaccuracies may be eliminated without necessitatingstoppage of the moving parts.

An additional object of the invention is to provide an apparatus whichcan be readily adjusted to deliver an equalized body of tobacco or otherowable solid material at a higher or lower rate.

A concomitant object of the invention is to provide an apparatus whereinthe material to be treated is invariably sealed from the atmosphere, atleast along the major part of its path through the apparatus, so thatthe expulsion of moisture or other treatment is localized in that areawhich is intended for such treatment.

Still another object of the invention is to provide a tobacco drying orconditioning apparatus which can utilize certain component parts ofconventional conditioning apparatus, which occupies little room, whichcan treat tobacco at a desired rate, and which can be adjusted in morethan one way to insure rapid elimination of inaccuracies in the feed oftobacco into the drier.

Briefly stated7 one feature of our present invention resides in theprovision of an apparatus for treating flowable material, particularlyfor expelling surplus moisture from particles of tobacco leaf stock. Theapparatus cornprises a feed for advancing a stream of flowable materiallengthwise, first conveyor lmeans including an inlet for receivingmaterial from the feed, an outlet, and means (preferably including anair lock) for converting the material which is received through theinlet into successive batches containing equal amounts of material andfor discharging such batches seriatim into the outlet by simultaneouslysealing the inlet from the outlet against uncontrolled flow of air, andsecond conveyor means comprising a preferably trough-shaped conveyingmember having an intake end which is preferably sealingly coupled withthe outlet of the first conveyor means and a discharge end which isdistant from the intake end. The second conveyor means further comprisescombined advancing and equalizing means for (a) advancing the batches inthe conveying member from the intake end toward the discharge end sothat such batches form a continuous carpet or mat of abutting batchesextending from the intake end to the discharge end of the conveyingmember, and for (b) simultaneously equalizing the mat so that, at leastwhen it reaches the discharge end of the `conveying member, eachsuccessive increment of the mat has the same height and width andcontains the same or substantially the same amount of material.

The discharge end of the conveying member may feed such successiveincrements into the lower portion of a preferably vertical duct whichreceives a current of hot air or another suitable gas through its lowerend so that the ascending current of hot gas entrains the particles ofmaterial which is admitted through the discharge end of the conveyingmember and treats such particles while they advance with the currentupwardly and through the duct.

vThe novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved apparatus itself, however, both as to its construction and itsmode of operation, together with additional features and advantagesthereof, will be best understood upon perusal of the following detaileddescription of a specific embodiment with reference to the accompanyingdrawings, in which:

FIG. 1 is a longitudinal central vertical section through an apparatusfor treating'tobacco;

FIG. 2 is a transverse vertical section as seen in the direction ofarrows from the line II-II of FIG. 1; `and FIG. 3 is a fragmentaryhorizontal sectional view as seen in the direction of arrows from theline III- III of FIG; 2.

Referring to the drawings in detail, the apparatus of our inventionserves to treat destalked shredded tobacco leaf stock. The treatmentconsists in that the apparatus expels from tobacco a certain amount ofmoisture so that the moisture content of material leaving the apparatusis within a predetermined optimum range such as is desirable when thetobacco is stored in Vbales or barrels for curing or when the tobacco isfed into a cigarette or cigar making machine.

The apparatus comprises a drier here shown as an upright duct 2 ofrectangular (preferably square) crosssectional outline. The lower end ofthe duct 2 is formed by an upwardly diverging cone 8 which is connectedwith a supply pipe 4 serving to admit a current of hot air or anothersuitable gaseous medium from a heater 4a. The upper end of the duct 2 isconnected with a discharge pipe 6 which conveys the current of hot gasto a suction fan 6a.

The lower portion of the duct 2 is further connected with the dischargeend of a horizontal conveying member or trough 14 forming part of aconveyor B which discharges successive increments of an equalizedtobacco carpet or mat M so that such increments are entrained 'by thecurrent of hot gas and ascend therewith into the discharge pipe 6. Theparticles of tobacco are relieved of surplus moisture during travelthrough the duct 2 and are separated from the current of hot gas beforethe latter enters the inlet of the suction fan 6a. It will be seen thatthe discharge end 20 of the trough is located at a level above the cone8 so that successive increments of the mat M enter a current of hot gaswhose velocity has decreased in response to expansion during travelthrough the cone.

The trough 14 is of rectangular cross section and its width increasesfrom the intake end 52 toward the discharge end 20. This is clearlyshown in FIG. 3. The width of the discharge end 20 approximates thewidth of the side wall 10 of the duct 2. This discharge end 20 isreceived with clearance in an opening 12 provided in the side wall 10`and is sealingly coupled with this wall by an elastic sleeve 22 ofrubber or synthetic plastic which is slipped onto the trough 14 and hasa radially extending ange secured to the wall 10 by bolts, screws orsimilar fasteners 24.

The Vbottom wall of the trough 14 carries two pairs of lugs 15, 17 whichare respectively connected with the upper ends of links 16, 18. Thelower ends of the links 16, 18 are connected with stationary brackets70, 71. Each link is pivotable about two horizontal axes so that thetrough 14 can be vibrated by a device 25 including an electric motor 26driving an endless belt 28 which drives the input shaft of avariable-speed transmission 30. The output shaft of the transmission 30carries a wheel 33 provided with an eccentric pin for one end of amotion transmitting rod 32 the other end of which is articulatelysecured to a bracket 34 at the underside of the trough 14. When themotor 26 is started, the push rod 32 vibrates the trough 14 back andforth to thereby advance the mat M lengthwise toward the discharge end20.

The side walls of the trough 14 are provided with transparent ortranslucent windows 36 which enable the 0perators to inspect theformation of the mat M and the progress of tobacco particles toward thedischarge end 20.

The other conveyor A of the apparatus shown in FIGS. 1 and 2 receive acontinuous tobacco stream T from a feed including an endless feed belt58. The right-hand end turn of the belt 58 (as viewed in FIG. 2)discharges tobacco into a hopper 57 which constitutes the inlet of theconveyor A. The outlet 46 ofthe conveyor A resembles a vertical shaft ofrectangular cross-sectional outline and is sealingly coupled to theintake end 52 of the trough 14 in a manner as" shown in FIG. 1. Theconveyor A further comprises a cylindrical housing 38 which extendsbetween the inlet 57 and outlet 46 and accommodates an air lock (alsocalled star feeder) 41. This air lock 41 comprises a horizontal shaft 40which is parallel with the direction of movement of the mat M in thetrough 14. The housing 38 is mounted on a stationary framework 42 whichalso supports a variable-speed electric motor 44 for the shaft 40. Theair lock 41 further comprises a cylindrical sleeve 40a which isconnected with the shaft 40 and carries four equidistant vanes or blades64 located in planes including the axis of the shaft 40 and havingaxially parallel outer edges which travel along the internal surface ofthe housing 38 so as to prevent uncontrolled ow of air from the inlet 57to the outlet 46. The air lock 41 is driven in a counterclockwisedirection (see the arrow 72 in FIG. 2) and the vanes 64 define betweenthemselves four cells 66.

The coupling between the outlet 46 of the conveyor A and the intake end52 of the trough 14 comprises an elastic sleeve 48 which is slipped ontothe intake end 52 and is fixed to the outlet 46 by bolts, screws oranalogous fasteners 50. The sleeve 48 allows for vibration of the trough14 but prevents uncontrolled ow of air into or from the interior of theoutlet 46 and trough 14.

The belt 58 is driven by a second variable-speed electric motor 60 andits driven roller 58a is mounted in the side walls 54, 56 of the inlet57.

The sleeves 22 and 48 insure that the interior of the trough 14 iscompletely sealed from the atmosphere. This will be readily understoodsince the air lock 41 of the conveyor A seals the inlet 57 from theoutlet 46 and the discharge end 20 communicates solely with theconditioning chamber defined by the duct 2. Another important advantageof the sleeves 22 and 48 is that they cannot communicate vibrations ofthe trough 14 to the duct 2 and/ or conveyor A.

The operation of our apparatus is as follows:

The motor 60 for the endless feed belt 58 is adjusted so that the beltadvances the tobacco stream T lengthwise at a desired speed. The speedof the motor 44 for the air lock 41 is adjusted in dependency on thespeed of the motor 60 (or vice versa) so that each successive cell 66 ofthe conveyor A receives a predetermined amount of tobacco whereby suchtobacco forms a batch 74 which travels through the housing 38 (arrow 72)and descends by gravity through the outlet 46 and into the intake end 52of the trough 14, i.e., onto the left-hand end portion of the trough, asviewed in FIG. 1.

The variable-speed transmission 30 of the vibrating device 25 isadjusted in such a way that the trough 14 removes a batch 74 from itsintake end 52 before the conveyor A discharges the next batch 74a. Thus,successively delivered batches 74, 74a, 74h form the aforementionedcarpet or mat M wherein the regions where the adjoining batches abut arecharacterized by relatively shallow transversely extending grooves orfurrows 78. Since the width of the trough 14 increases toward thedischarge end 20, and since the trough is continuously vibrated by thedevice 25, the depth of the grooves 78 decreases gradually and suchgrooves should normally disappear before the corresponding portion ofthe mat M reaches the discharge end 20. In other words, the vibratingdevice 25 can besaid to'constitute a means -for advancing the mat Mlengthwise of the trough 14 and for simultaneously equalizing the mat sothat each such increment of the mat which enters the lower portion ofthe duct 2 contains the same or substantially the samefamount oftobacco. FIG. 1| shows clearly that the groove or furrow 78 between therearmost batch 74b and the preceding batch-74a is substantially deeperthan the groove or furrow 77 between the foremost batch 74 and the batch74a. The variable speed drives (transmission 30 and motors 44, 60) forthe conveyors B, A and the feed belt 5S are adjusted in such a way thatthe leading end of a freshly admitted batch 74b immediately abutsagainst the trailing end of the preceding ybatch 74a so that there areno voids between successive batches. The person looking through one ofthe windows 36 can readily observe the equalizing operation and, if suchequalizing operation is not entirely satisfactory, adjustment of thetransmission 30, motor 44 and/or motor 60 can rapidly eliminate anyinaccuracies so that each successive increment of the mat M willinvariably contain the same amount of tobacco before such incrementsreach the discharge end 20. The fact that the trough 14 diverges towardits discharge end also contributes to highly satisfactory equalizingaction. Furthermore, and since the trough 14 vibrates at all times, anyagglomerations of tobacco particles which are stillpresent in the intakeend 52 will disappear on their way toward the discharge end 20 so thatthe duct 2 receives loose tobacco particles each of which is fullyexposed to the moisture-expelling action of the current of hot gasadmitted'byV the supply pipe 4. As stated before, particles of tobaccotraveling upwardly through the duct 2 and' into'the discharge pipe 6will be separated from the current of hot gas before the latter entersthe inlet of the suction fan 6a. Such separation of treated tobacco canbe carried out in a very simple way'by reducing the speed of thecurrentof hot gas so that the solid fraction can descend Vby gravity. Thedischarge end 20 of the trough 14 discharges tobacco into the lowerportion of the duct 2 so thatfsuch tobacco is brought into contact withair which is still hot and is capable of expelling requisite amounts ofmoisture. Also, such admission of tobacco into the lower portion of theduct 2 enables the current of hot air to disperse the particles acrossthe full width of the duct so that each such particle is fully exposed.

The windows 36 also enable the persons in charge to reduce the speed ofthe transmission 30 or to increase the speed of the feed belt 58 if thesuccessively delivered batches 74, 74a, 74b do not touch each other. Thepersons in charge will reduce the speed of the motors 44 and 60 if thesuccessively delivered batches over-lie each other, i.e., if theparticles discharged by a lirst cell 66 are not fully removed from theintake end 52 prior to admission of y'particles from the next-followingcell 66.

The adjustablity of the drives for the feed belt 58 and conveyors A andB further enables the personnel to regulate4 the drying action in a verysimple and accurate way. The amounts of tobacco admitted to the duct 2per unit of time will determine the extent to which the current of hotair is cooled on contact with tobacco, On the other hand, themoisture-expelling action of the current of hot gas is dependent on itstemperature. Thus, by regulating the speed of the mat M along the trough14, and by regulating the amounts of tobacco contained in successiveincrements of the mat, the operators can regulatei the drying action inthe duct 2. The amounts of tobacco in successive increments or unitlengths of the mat M can be regulated by proper adjustment of the motor60 for the feed belt 58.

An important advantage of an air lock whose shaft 40 rotates about ahorizontal axis which is parallel to the direction of movement of themat M is seen to reside in that such an air lock can form and dischargebatches (74, 74a, 74b) which contain identical or nearly identicalamounts of tobacco and that each batch has the same shape as thepreceding batch. Therefore. the batches 74, 74a, 74b can be readilyconverted into a continuous mat which is then fully equalized duringtravel in the trough 14. It will Kbe seen that the leading end of themat M which is admitted into the lower portion of the duct 2 has arelatively small height. This is of advantage because experimentscarried out `with our apparatus indicate that a relatively wide rnatofsmall height can be fed more uniformly than a higher mat and thatsuccessive increments of a wide but flat mat can be more readilyentrained and dispersed by the current of hot gas flowing upwardly inthe duct 2.

Without further analysis, the foregoing will so vfully reveal the gistof the present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecie aspects of our contribution to the art and, therefore, suchadaptations should and are intended to be comprehended within themeanining and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is:

1. Apparatus for treating owable material, particularly for treatingtobacco, comprising a feed for advancing a stream of materiallengthwise; rst conveyor means comprising an inlet for receivingmaterial from said feed, an outlet, and means for converting thematerial which is received through said inlet into successive batchesand lfor discharging such batches into said outlet by simultaneouslysealing said inlet from said outlet; and second conveyor meanscomprising a conveying member having an intake end connected with saidoutlet and arranged to receive successive batches from said rst conveyormeans and a discharge end distant from said intake end, said secondconveyor means further comprising means for advancing said batches insaid conveying member from said intake end toward said discharge end sothat such batches form a continuous mat which extends from said intakeend to said discharge end and wherein successive batches compriseportions of increasing height, and for simultaneous-ly equalizing saidmat so that, on reaching said discharge end, each successive incrementof the mat contains substantially the same amount of material.

2. Apparatus as set forth in claim 1, Iwherein the means for convertingmaterial into batches comprises an air lock having a member rotatableabout an axis which is parallel with the direction in which the matadvances in said conveying member.

3. Apparat-us as set Iforth in claim 1, wherein said conveying member isan elongated trough and wherein said mat `advancing and equalizing meanscomprises a device for vibrating said trough.

4. Apparatus as set forth in claim 1, further comprising coupling meansproviding a uidtight connection between said outlet and said intake end.

5. Apparatus as set forth in claim 1, further comprising independentvariable-speed drive means for each of said conveyor means.

6. Apparatus as set forth in claim 1, further comprising l independentvariable-speed drive means for at least one of said conveyor means andfor said feed.

7. Apparatus as set forth in claim 1, lwherein said conveying member isprovided with at least one transparent portion to permit visualobservation of the formation and equalization of said mat.

8. Apparatus for treating tobacco, comprising a feed for advancing astream of tobacco lengthwise; first conveyor means comprising an inletfor receiving tobacco from said feed, an outlet, and means forconverting tobacco which is received through said inlet into successivebatches and for discharging such batches into said outlet bysimultaneously sealing said inlet from said outlet; second conveyormeans comprising an elongated trough having'an intake end connected withsaid outlet and arranged to receive successive batches from said trstconveyor means and a discharge end distant from said intake end, saidsecond conveyor means further comprising a device for vibrating saidtrough to thereby advance said batches in the trough from said. intakeend toward said discharge end so that such batches form a continuousmat'extending from said intake end to said discharge end, and tosimultaneously equalize said mat so that, on reaching said dischargeend, each successive increment of the mat contains substantially thesame amount of tobacco; and a drier arranged to receive tobacco from thedischarge `end of said trough, said drier comprising an upright. ducthaving a lower portion sealingly connected with said discharge end. toreceive successive increments of the equa-lized mat, and means foradmitting a current of hot gas into said duct below said lower portionthereof so that the current rises in and entrains the particles oftobacco through said duct. Y

9. Apparatus for treating owable material, particularly for treatingtobacco, comprising a feed for advancing a stream of materiallengthwise; rst conveyor means comprising an inlet for receivingmaterial from said feed, an outlet, and means for converting thematerial which is received through said inlet into successive batchesand for discharging such batches into said outlet by simultaneouslysealing said inlet vfrom said outlet; and second conveyor meanscomprising an elongated trough located in a substantially horizontalplane and having an intake end connected with said outlet and arrangedto receive successive batches from said rst conveyor means and dischargeend distant from said intake end, said second conveyor means furthercomprising a device for vibrating said trough to thereby advance saidbatches in said trough from said intake end toward said discharge end sothat such batches Iform a continuous mat extending from said intake endto said discharge end, and to simultaneously equalize said mat so that,on reaching said discharge end,

eachfsuccessive increment of-vthe mat containscsubstantially the sameamount of material. f i! y'. 10. Apparat-us for treating iiowablematerial, particu- Iarly for treating tobacco, comprisinga feedv'foradvancing a streamxof Imaterial lengthwise; first .conveyor meanscomprising an 'inlet for receiving material from said feed, an outlet,and means for converting the material' which lis received through' saidinlet into successive batches andior discharging such batches into saidoutletv by simultaneously sealing said inlet from said outlet; andsecond conveyor means comprising anelongated trough having. an intakeend connectedl withrsaid outletv and arranged toy receive successivebatches from said rstconveyor meansI and a discharge end `distant fromsaid intake end, theawidth of said troughincreasing in a directionfrom-the intake end :toward the `discharge end thereof and saidsecondconveyor means `further comprising a device for vibrating said trough tothereby advance said batches in said trough from said intake'end towardsaid discharge end so that such'batches form acontinuous mat extendinglfrom said intake end to saiddischarge end, and to simultaneouslyequalize said mat so that, on reaching said discharge end, eachsuccessive increment of the matcontains substantially the same amount ofmaterial.

References Citedy UNITED STATES PATENTS 694,958 3/1902 Gals'chtot 34-164'790,162 5/1905 Trump.. p 2,363,281 11/1Q44.Am01d 34-10 2,508,8845/1950l Hereng 34-164 XR 2,563,332 9/1951 Genovese gt -198-59 3,228,5171/19615 Yeasting 198-220 A. D.' HERRMANN, Assistant Examinar.

